Self-sealing releasable coupling



May 15, 1951 D. F. STRANBE'RG Re. 23,365

SELF-SEAQING RELEASABLE COUPLI-NG Original Filed Oct. 1, 11.9477

www, LW

D an EEranh eral- @Mm/we/ Ressued May 15, 1951 SELF-SEALING RELEASABLE COUPLING Don F. Stranberg, Libertyville, Ill., assignor to Charles L. Conroy, Waukegan, and Walter Fritsch, Libertyville, Ill.

Original No. 2,461,705, dated February 15, 1949,

Serial No. 777,229, October 1, 1947. Application for reissue October 17., 1949, Serial No.

17 Claims.

yreleasable couplings for fluid pressure lines.

In conventional couplings of the foregoing type, two serious objections are encountered. One occurs in obtaining separation of the coupling at a predetermined pull-strain, due to variation in the line pressure, while the other results from dimculty in unseating the valves against the line pressure in order to connect the coupling members. l

The present invention has for its object to overcome the foregoing objections by the provision of a comparatively simple and inexpensive releasable self-sealing coupling, which releases itself at a predetermined pull-strain, and which may be easily connected without the aid of tools, regardless of the amount of pressure within the line.

Incidental to the foregoing, a more specific object of the invention is to provide a coupling Matter enclosed in heavy brackets appears in the original patent but tonus no part'of this reissue specification; matter printed in italics indicates the additions made by reissue.

utilizing a predetermined proportion of the line pressure to oppose the seating force of said pressure on the valves, whereby the same may be unseated by manual force without the aid of tools, irrespective of the line pressure.

Another object of the invention is to provide a self-sealing releasable coupling with spring urged holding means aiected by pressure force within the line substantially equalto the parting force of said pressure, whereby the coupling is released by sufficient pull-strain to overcome the spring tension, plus friction, on the holding means, irrespective of the amount cf pressure in the line.

In addition to the foregoing, other objects will appear as the description proceeds, and while the accompanying drawing illustrates one completephysical form of the invention constructed in accordance with the best mode so far devised, it is to be understood that changes in the precise embodiment of the invention are contemplated within the scope of the appended claims.

In the drawing: Y r

Fig. l isa half elevational and half sectional view of a coupling incorporating principles of the present invention, and illustrating the parts With particular reference to the drawing, the self-sealing releasable coupling illustrated comprises male and female coupling members I and 2,y respectively, having axial iiuid passage and provided with threaded end connectors 3 for attachment to .conventional fittings of a iiuid pressure hose or conduit (not shown).

The female coupling member 2 is provided at its forward end with a restricted cylindrical bore I, for reception of a reduced cylindrical end 5 of the male coupling member I, which is sealed within the bore of kthe female coupling member 2 by an 0 ring Ii, or other equivalent packing.

Sldably mounted within enlarged bores 1, formed in both male and female coupling members I and 2, are self-sealing valves 8 of identical structure, and consequently a description of one valve will sufce for both.

Each valve 8 consists of a shank 9, which, in the unseated position of the valves shown in Fig. 1, abuts the shank of the valve in the adjacent coupling member. A valve head IVI), carried by the shank 9, is provided on its seating face with a restricted annular groove II for confinement of a sealing ring I2 adaped to engage a tapered internal valve seat I3, formed between the enlarged bore 1 and the reduced end bore in each of the coupling members.

Extending axially from the valve head III is a cylindrical sleeve I4, slidably journaled within .the connector 3 threaded into the end of the coupling member and sealed by an O ring I1. Intermediate its ends the sleeve Il is provided with an external piston flange I5, which in turn is sealed within the enlarged bore 1 of the coupling member by an 0 ring I6. To afford communication between the interior and exterior of the sleeve I4, between the front face of the piston flange I5 and the valve head III, thesleeve is provided with a plurality vof radial openings I8.

For the purpose of releasably latching the separable coupling members I and 2 in the assembled relation shown in Fig. 1, a union sleeve III, which snugly receives the female coupling member 2, is provided with an internal end flange 20 contracted into a periferial annular groove 2"I formed on the malel coupling member I to rotatably retain the sleeve I9 thereon. The inner face of the sleeve I9 is provided with an annular groove 22 for reception of a plurality of annularly spaced piston detents 23, slidably mounted in radial bores 24 formed in the female coupling member 2, and communicating with the axial passage of the member through openings 25. The

3 piston detents are sealed within the radial bores 24 by packing rings 2l. and urged outwardly t0 engage the annular groove 22 provided in the union sleeve I! by helical coil springs 2l.

A coil spring 21, surrounding the sleeve Il and Y 4 R To reduce the force required to unseat the valves I to a minimum,` allow manual connection of the coupling members without the use of tools, the Journal sleeves Il carried by the interposed between the rear face of the piston or conduit of any type, by means of end connectors 3, which in turn are threaded, or secured in any suitable manner, in the ends of the separable maleand female couplings I and 2 respectively.

As shown in Fig. 1, when the coupling members are joined in operative position, the reduced end I of the male coupling I extends into the end bore I of the female coupling 2, to provide a swivel and slidable connection securely sealed by the ring i. Y

In their connected positions the coupling members are latched against axial separation by the spring urged piston detents 23, carried by the coupling member 2 and normally projected into the internal annular groove 22 formed in the. union swivel sleeve Il secured on the male coupling I.

Obviously, when the coupling members are joined, the abutted shanks 9 of the valves 8 serve to hold the valves oil of their respective seats,

permitting pressure fluid to flow through the coaxial passages in the coupling members. Inherently, the fluid pressure ln the line exerts a parting force upon the coupling members, and under conditions of high pressure this force is increased proportionately;

However, ln the present instance, the holding piston detents 23 are affected by line pressure because of the communicating, openings 25 between the fluid e ln the. coupling member 2 and the piston bores 24. thus increasing or reducing the holding force in xed proportion to the parting force. While this proportion may be varied within a certain range, it is proposed to substantially equalize the pressure areas of the piston detents with those of the coupling member affected by the parting force. Consequently, only sufliclent tensional or pull strain is required on the conduit or coupling members to depress the and overcome friction in order to separate the coupling. The foregoing parting strain is accurately predetermined and constantly main-y tained through| fixed tension of the springs 28.

throughout variations in the line pressure.

In connection with the self-sealing function of the coupling, it will be apparent thatdlpon parting of the coupling members, existing pressure in each section of the line will act upon the respective valves l, forcing the same upon their seats Il to seal the axial fluid passage in the coupling members.

As suggested in the preceding description of the struchire illustrated, under conditions of low presure, and the occurrence of friction between the valve journals and' coupling members, the line pressure may be insufficient or slow in closing the valves, with resultant excessive fluid loss.

This'is overcome by the springs 21, which aidv effecting closing action of the valve.

detents against the tension of the springs 2B' valves l are provided with the piston flanges I l,

the 'function of which might best be explained with reference to Fla'. 4, which dlagrammatically illustrates the principle of operation.

Here it will be noted that one face of the piston ange I` is affected by the line pressure passing through the radial openings IlA in the sleeve Il.

Obviously, pressure against the rear surface of the valve head and valve sleeve within the area A, tends to' force the valve upon its seat, while pressure withln'the area B ailecting the flange Il, opposes the closingl force. Therefore. the area of the aected surfaces of the flange I5 is less than the ail'ectedA valve surfaces in the area A, as a result of which the proportionate differential between the two forces functions to hold the valve upon its seat.

The above dierential seating force is prede' termined to the extent that it permits manual unseating of the valve under-a maximum pressure capacity in the line, whereby the coupling members may be readily connected by forcing the two together by hand. without the aid of a wrench, vise, pry-bar, or special tool, such, as required in conventional releasable couplings. The bleed opening l shown in Fig. 4, merely serves to prevent a pressure lock behind the piston flange I5, and represents the equivalent of leakage occurring through the threads in the connection between the coupling members and connectors I.

From the foregoing explanation, considered in connection with the accompanying drawing, it will be apparent that a comparatively simple, compact and highly effective self-sealing releasable and swivel coupling has been devised, which is separable upon an accurately predetermined tenslonal or pull-strain, and which may be easily connected by hand against the maximum pressure capacity of the conduits.

While the invention has been described in considerable detail as applied to the coupling, released upon tensional strain, that feature relating to reduction of force required for unseating the sealing valve is applicable to'couplings connected by a union nut, inasmuch as it permits the nut to be threaded on -the coupling by hand,

instead of requiring a wrench or tool.

Although the novel feature of the present invention pertaining to the self-sealing valves has been illustrated and described in considerable detail, as applied to both coupling members (1 and 2) for most epiciently connecting the coupling members under usual conditions, it will be obvious that a self sealing valve of the present type may be advantageously employed in only one of the coupling members, by providing a manually controlled pressure cut-o1? in the opposite end of the line.

For example, when a releasable coupling is installed in a line between a tractor equipped to create fluid pressure, and a drawn implement affected by the pressure fluid, the tractor may be provided with a manually controlled pressure fluid cut-of, actuated by the operator upon release of the coupling. Under such condition pressure would be relieved in the tractor line but retained in the implement line. Therefore, avalve of the present type included in the implement end of the coupling only, would be sumcient to allow manual connection of the coupling without the laid of tools in the manner explained above. y e

Furthermore, the principle of the presentlatching or holding mechanism maybe used in releasable couplings for fluid pressure lines `in which there is no provision for sealing, the coupling members upon disconnection, 'such as in air-brake conduits in which titre/:line pressure must be released upon separation 'of the couplings. Although specificV proportional pressure has been' mentioned throughout the specifications for the purpose of illustration, it is to beunderstod that these may be varied' within certain ranges without departing from-the principles *of the 1nvention.,y it being merely necessary that the pressures function to accomplish the purposesand advantages set forth.' l 'A I claim: l. A self-Sealing releasable coupling for fluid pressure lines comprising, a pair of separable` coupling members, means forV releasably-holding said membersfin coupled relation, a pressurey seated valve carried byyeach of said coupling members for sealing said members rwhen 'separated, means for unseating` said valves upon connection of said coupling members, and means associated with each of said valves [and affected by a predetermined proportionate force of. the

line pressure yto oppose the seating force of said pressure, the force of said opposing pressure being less than said seating pressure'to allow unseating ofthe valve bymanual force witho'ut'the aid `of tools] on the pressure side'ofv-the-valve seats'for determining the seating fore `'per-ted upon `said valves by the line pressure, s dfnieans `being affected by atmospheric pressurefpposed by a proportionate force of the linepress'u're tending to unseat said valves, the unseatingjforce being less than the seating force.

[2. A self-sealing releasable coupling for fluid pressure lines comprising, a pair of separable coupling members, meansfor releasably holding said members in coupled relation, a pressure seated valve carried' by eachvof said coupling members for sealing said members when separated, means for unseating said valves upon connection of said coupling members, and means associated with each of said valves providing opposed suriaces of different area aflected by the line pressure to establish a differential force urging the valve upon its seat] 3. A self-sealing releasable coupling for fluid pressure lines comprising, a pair of separable coupling members, means for releasably holding said members in coupled relationfa pressure seated valve carried by each of` slaidgcoupling members for sealingsaid members when separated. means for unseating said valves upon connection of said coupling members, and [pistons] a piston associated with each of Ysaid valves [and affected by a proportionate force of the line pressure to oppose the closing force of said pressure upon said valve, said opposing force being less than said'seating force] on the pressure side of the valve seats for determining' the seating force exerted upon said valves by the lline pressure, said pistons being afected by atmospheric pressure on one side and opposed by'a proportionate force of the' line pressure tending to `unseat said valves, theunseating force being less than the seating force. l s Y' o '4. A self-sealing releasable coupling for fluid pressure lines comprising, a pair of separable coupling members having co-axial fluid passage.

, l. means for' releasably holding said members in 6 coupled relation, a pressure seated valve slidably mounted in the fluid passage of each of said coupling members for sealing said members when separated, said valves having abutted engagement for holding them off of their respective seats, a cylindrical sleeve carried by each of said valves, and an annular piston flange provided on said sleeve and operable within the fluid passageway of said coupling member, said piston flange being affected by a proportionate force of the line pressure to oppose the closing force of said pressure upon said valve, said opposing force being less than said closing force.

5. A releasable coupling for fluid pressure lines comprising, a pair of separable coupling members upon which the line pressure'exerts a kparting force, means actuated by line pressure for holding said coupling members in connected relation with a force opposed to and substantially equal to said parting force, and springtensionmeans augmenting said pressure holding force in urging said holding means into operative position.

6. A releasable coupling for fluid pressure lines comprising, a pair of separable coupling members upon which the line pressure exerts a partline pressure for holding said coupling members in connected relation with` a force Opposed to and substantially equal to said parting force, spring tension means augmenting said pressure holding force in urging said holding means into operative position, a pressure seated valve carried by each of said coupling members for "sealing said members when separated, means for unseating said valves upon connection of said coupling members, and means associated with each of said valves and affected by a predetermined proportionate force of the line pressure to oppose the seating force of said pressure, the force of said opposing pressure being less than said seating pressure to allow unseating of the valves by manual force without the aid of tools.

8. A self-sealing releasable coupling for fluidl nection of said pressure members, and means associated with each of said valves providing opposed surfaces of different area affected lby the line pressure to establish a differential force urging the valve upon its seat.l

9. A self-sealing releasable couplingfor fluid pressure lines comprising, a "pair of separable coupling members upon which the line-pressure exerts a partingforce," means actuated by vthe line pressure for holding said `coupling members j -to andsubstantially equal to said parting force,

in connected relation with a force opposedy `to spring tension means augmenting said pressure and substantially equal to said lparting force, holding force in urging said holding means into spring tensionv means augmenting said pressureV operative'positiom a pressure seated valve slidholding means for urging said holding means I rablym ounted in the fluid passage of each .of said into operative position, a pressure seated valve coupling members forsealingsald members when carried by each of said coupling membersA for` 8eDilr3ted.Said` valves having butbed 8118388- sealing said members when separated, means for kInerits11` r "holding them oi! of their respective y unseating said valves upon connection of said Seat'swhen'the coupling members are joined, a

coupling members. and means associated with 10 C'yliridlial "sleeve, carried by each of said valves t each of said valves providing opposed surfaces ot and 1in annular-111511011 ige Provided 0nr Said din'erent area affected by the line pressure toes-` sleeveand operable within the said fluid passagetablish a dierential force urging' the valve upo n. t wai Of Sidouplingmember, Said Pision mime 10. A self-sealing releasable coupling'-v for -uid l1 5 Iinejpressurej'to oppose the closing force of said Pressure lines. comprising, a pair of separable p11? ssl.I refll'fiori Said valve, said opposing force-be coupling members upon which the line pressure ing 1SS-hHh-Said ,Closing vfOleexerts a parting force.l a nuid pressure 'piston in j 14K-A selffseelins releavsable coupling for fluid communication with the line pressure ior'holding pressure YCOmPI'iSng; 9" pail' 01' separable s'aid coupling members in'connected relation'with 2n" eouplingmembers upon which the llne pressure a force opposed to and substantially equal to said, eXertSa Pal-'tuig f0rCe. Said 60111111118 members Y parting force, aspring augmentingthe pressure 'hgVIlE-Coaxialyuid Passages. a fluid 41311288117112* force of said piston@ urge-the pign-1nt5pppistonin-communicationwith the linepressure erative holding. position, a pressure 'seated'valve fOr holding Said coupling members in connected carried by veach of said eou'pnng members forja yieliitiorrwith a force Opposed t0 and substan-V seaiingsaidzmembers when separated, meansfor Y tialiy-equal to'said parting rforea'aispriiis aus,-

"I gisting said valves umn connection Qf, said the pressure'force on said piston to urge coupling members, landl means associated with the Same iIltQQpelfatiVe holding DOSitiOIl.' a PreS- each of 'said Lvalves providing vopposed surfacesv f Silldi Valve.".Slidilblyv mPuIted 111 the fluid coupling members upon which the line pressure 3;

of .different area affectedby the line Pressure-toi@ PWM@ QfChfof v said follpling lmembers for establish a timex-egual force urging the' *all/ 'YSealing.sind,PassagesA Whensaid couplings are upon'itsseat.

separatedpsaidf valves Yhaving abutted engage- 1'1. A seifiseaungjr'aeasasie.coupling frnuid, `f"merits"fiorg-hlf'iinsf them ofi of their respective." y pressure lines comprising, a pairof Vseparable, rvSmilie' When Said 20111111118 member-S are .iOiIiedfnv url v'cylindricalsleeve carried'by each of said valves.'l

exerts aparting force, means actuated by theline and "an anni-llarpi-SOII Hanse provided on said pressure'for holding said coupling members in 1 516W? ndbpeiblefwithn the fluid passage 0f z'- .tension meansA augmenting said pressure ho'ld 40 Sure QPPOSe *the v(905mg fore? 0f said Pressl1` nforce in ur'ging/Sadholding'meansintqopupon` said valve, said opposing force being less connected relation with a forceopposedtoand .-iid'v 00m-)1111! member, saidPiSOIi' flangebeln substantially equal to' Saidparting fome, spring aected by Ya proportionate force of the line 'pres.`

erative position, a pressure seated valve carried 211311 saidzclosing fome! said members ywhen separated, means forl seatlngs'aid coupling members; and ,pistons assoji 1 091l1l1illil'-mmbm fr flfii'ir for Telellsabll/ hldilg elated with each of said'val'ves vand,aii'ec' ted by al .Seidl members ,.-in Acmmled relation. a pressure proportionatetorce of the line pressure to jopj-f seatedpalue arriedby one of-saz'd'couplin'gmempose theclosing'force of said pressure upon 4saidl be'rs, f Or'ifsealiJiyf-Said-, member when" Separated.

@pressure linescomprising; a' pair of separable valve, said opposing force beingle'ss, thank Said. 'l means l,for gnseatngzsaid iuzlveuponv connectionv v 50 o'fsaidycoupling members, and means associated 12. Aiself-sealing releasable couplingi'or uid wth'saidivaloe on the pressure side of the valve .pressure-lines'comprising, a pair of separable cout' seaty for determining `the seating force ,ezertcd pling me'x nber s upon which the linepressurefexf upon saidvalue bythe line z nessure, said means ertsfa parting force, a fluidxpressure `pistonfin be'inofaffected 11g/.atmospheric pressure opposed comlr'iunication with the line pressureiorhold- 55 Alai/ a proportionte forcof theline pressuretend-` ving saidcoupllng members in connected relationv ing t0 unscatfsaid valve; the un$elltn910e5-flwitlia force vopposed to and substantially equal`l` inglesa-than the seating force.

` pressure on said piston to urge thepi'stonyinto to said parting force, a spring augmenting thev operative holding position, .a presm Y'seated 'onme'mbers in coupled relation, azpressure s eated coupling' .members,j and pistons associatedfwlthj each of saidvalves and affected by;a `proportionhaving coaxial iluid passages, means actuated l6.`4 seul-sealing vreleasable coupling for pressure.jlnesjcompristng, a pair offseparable valve carried byeach of said'couplingmembes '.fvaluecarried by one ofsaid coupling l'members for sealing said memberstwhen separated, `means -v for unseating said valves upon connectionr f said.

-. .coup

,atev vforce of the line pressure to oppose thelcl'osl than .saidv seating force."

exerts a partinglfforce, said lcoupling. xn'el'r'ibers holding lsaid members in the line pressureiorholding sa'idcouplingme bersin'connected'relation with a'ior ?opposed ,e invit jfofr, sealinasaid member when sepjorealing said member .when separated, l fffe'runseatiiia said ualve'uponconneetion of jsaidf,

'glme'mpera u ndfq. piston associated with@` saidvaluef'andaffected by a proportionate force" I 'es 'sufe ltofoppose the closing force fupon saidvalve, said opposing* aling i'eleasable coupling forjluai l comprising, a vpair of separabley having'A co-axial fluid passages;`

uid'passage one of said coupling arated, said valve having abutted engagement for holding it o# of its respective seat, a cylindrical sleeve carried by said valve, and an annular piston flange provided on said sleeve and operable within the fluid passageway of said coupling member, said piston flange being affected by a proportionate force of the line pressure to oppose the closing force of said pressure upon said valve, said opposing force being less than said closing force.

18. A self-sealing releasable coupling for jluidpressure lines comprising, a pair of separable coupling members upon which the line pressure exerts a parting force, means actuated by the line pressure for holding said coupling members in connected relation with a force opposed to and substantially equal to said parting force, spring tension means augmenting said pressure holding /orce in urging said holding means into operative position, a pressure seated valve carried by one of said coupling. members for sealing said member when separated, means for unseating said valve upon connection of said coupling members, and means associated with said valve and aected by a predetermined proportionate force of the line pressure to oppose the seating force of said pressure, the force of said opposing pressure being less than said seating pressure toV allow unseating of said valve by manual force without the aid of tools.

DON F. STRANBERG.

REFERENCES CITED The following references are of record in the le of this patent or the original patent:

UNITED STATES PATENTS Number Name Date 162,169 Hopkins Apr. 20, 1875 324,031 Lacey Aug. 11, 1885 442,621 Harris et al Dec. 16. 1890 486,001 Tnsle,V Nov. 8, 1892 592,461 Westinghouse et al. Oct. 26, 1897 968,532 B1e3ica Aug. 30, 1910 1,255,756 Jones Feb. 5, 1918 1,808,990 Langdon June 9, 1931 2 135,221 Scheiwel Nov. 1, 1938 2,296,170 Lockhart Sept. 15, 1942 2,299,193 Trautman Oct. 20, 1942 2,461,940 Sundstrom Feb. 15, 1949 

